The upper Messinian assemblages of fossil vertebrate remains of Verduno (NW Italy): Another brick for a latest Miocene bridge across the Mediterranean

A considerable amount of vertebrate remains have been found in the upper Messinian Cassano Spinola Conglomerates Formation, which crops out along the Tanaro River near Verduno (Piedmont). The fossil-bearing deposits were deposited during the third stage of the Messinian Salinity Crisis (5.55-5.33 Ma) in connection with the 'Lago-Mare' event. Sedimentological evidence indicates that the deposition of this Formation originated in a variety of fresh- and brackish-water environments. This is the most diverse Late Miocene faunal community found in NW Italy up to now, and includes remains of fish (cyprinodontiforms and putative lophiiforms), amphibians (bufonids, ranids), reptiles (testudinids, geoemydids, lacertids, anguids, varanids, agamids, amphisbaenians, scolecophidians, colubrids), birds (galliforms, accipitriforms and strigiforms) and mammals (proboscideans, perissodactyls, artiodactyls, carnivores, insectivores, rodents and lagomorphs). The tetrapod assemblages are consistent with the late Turolian age inferred based on sedimentological evidence and indicative of an open, semi-arid woodland savanna with at least modest, sparse fresh and brackish water bodies. The Verduno fossil assemblages share faunal similarities with coeval ones of southwest, central, and eastern Europe, as well as of peninsular Italy. Located at the crossroads between the two sides of the Mediterranean, northwestern Italy witnessed faunal exchanges between the different corners of the European continent. It was also on the access pathway to the Italian peninsula. The Verduno assemblage made it possible to track the migration of several taxa during latest Miocene across the whole southern Europe.